Magic Five

TimeLimit:1000MS  MemoryLimit:256MB
64-bit integer IO format:%I64d
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Problem Description

There is a long plate s containing n digits. Iahub wants to delete some digits (possibly none, but he is not allowed to delete all the digits) to form his "magic number" on the plate, a number that is divisible by 5. Note that, the resulting number may contain leading zeros.

Now Iahub wants to count the number of ways he can obtain magic number, modulo 1000000007 (109 + 7). Two ways are different, if the set of deleted positions in s differs.

Look at the input part of the statement, s is given in a special form.

Input

In the first line you're given a string a (1 ≤ |a| ≤ 105), containing digits only. In the second line you're given an integer k (1 ≤ k ≤ 109). The plate s is formed by concatenating k copies of a together. That is n = |ak.

Output

Print a single integer — the required number of ways modulo 1000000007 (109 + 7).

SampleInput 1
1256
1
SampleOutput 1
4
SampleInput 2
13990
2
SampleOutput 2
528
SampleInput 3
555
2
SampleOutput 3
63
Note

In the first case, there are four possible ways to make a number that is divisible by 5: 5, 15, 25 and 125.

In the second case, remember to concatenate the copies of a. The actual plate is 1399013990.

In the third case, except deleting all digits, any choice will do. Therefore there are 26 - 1 = 63 possible ways to delete digits.

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题目统计信息详细
总AC数146
通过人数132
尝试人数199
总提交量1058
AC率12.48%
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